Intermitent feedback loop?

Hi,

I've had a MKII Empeg for 7 years now. Recently some kind of intermittent feedback has started. It comes and goes when I hit bumps on the road. I've pulled the sled out and checked the wires and tried shaking them around while it was happening - it had no effect. I checked all of the signal cables and wiring to my amp, everything is solid.

I plugged the Empeg into a speaker system in my house - works perfect. Next I plugged my Treo into the RCA's the sled was using - works perfect. Plug the sled back in and drive about 200 feet, feedback loop started.

A strange thing happened when I had the RCAs unplugged from the sled but the radio was still playing on the Emped I could hear the song faintly in the background. Changing stations changed what played so it's directly related.

Suggestions? Known problems? Thanks in advance!

Dan

Maybe the wiring to/on your amp is faulty?

Check the ground wires for the amp?
It sounds like something might have wiggled loose after all these years.

Being able to hear the radio tuner while the RCA cables are unplugged seems to indicate inductive noise or a ground loop.

Make sure there is nothing loose rattling around inside the player.

Check the sled wiring for loose crimps.

Check: Every. Single. Wire. Between the player, its power source, the amp, its power source, etc., and triple check every single ground wire. Open the player and make sure none of its wiring harnesses have come loose or are chafing inside anywhere.

Look here and here for the starting point for noise and ground loop troubleshooting.

Make sure you've adjusted your amplifier input gains down, as described here in the section titled "Properly adjust the input gain level on the amplifier(s):"